(G) writes:

In article , (G) wrote:
In article , (G)
wrote:
In article , (G)
wrote:
In article M6GHi.3333$Ap2.2805@trndny05, "James Sweet"
wrote:

"G" wrote in message
. ..
I have a system that worked. Had a lamp and a ballast. It quit
working. I replaced lamp and ballast, check everything except the voltage
between the ends of the tube. The filiments light. My question, its a two
lamp
ballast that has two unused wires. Having only one lamp connected, could
this
cause a reduced starting voltage across the lamp. I am suspecting
some weak link and not a hard core problem.

greg

Are you sure the ballast is wired right? Most North American twin lamp
autotransformer ballasts wire the lamps in series, the output of the
secondary is on the red and blue wires, the yellow wires are only a small
winding to provide cathode heat to the middle cathodes.

Yellows on one side, one lamp to reds and another if present to blues on the
other sides. 120 vac. I checked voltages except the actual drive, supposed
to be about 380 vac unloaded. I will measure that next. I had to defeat
contacts to get access. Its all in a big hood. It worked, now it still does
ot
even with new parts. I don't imagine there is a problem with the socket since
the filiments light. Its also a UV lamp.

I wired up a strobe once. It would not work in the dark. As soon as you gave
it enough light it would fire.

I am reading the lamp FAQ.

The measurements on the orginal ballast are off. I may have a bad new ballast

I am looking at the orginal ballast and another single lamp with RR BBuWG

On the later I measure HV when the lamp in inserted, but there is
no HV open, and the lamp is a perfectly working model. I'm not sure I
understand the no HV concept. Its not present on the orginal non
working model 2 lamp ballast.

I ordered another ballast, slightly different. The second ballast didn't seem
to have enough oomph. I did read a open starting voltge almost 200 volts.
It just got loaded down with the tube even though its for a bigger tube ??

I had wonderd if a UV lamp has slightly different requirments, as I found
an old separate listing for Advance UV ballasts. Don't know.

Don't know for sure but a UV lamp is just a normal lamp without the
phosphor and probably in a quartz envelope?

BTW, how sure are you that the lamp is good? Sorry if this was mentioned
already.

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